I need to assign more than 10 managed policies to a permission set in AWS SSO

The "Managed policies per role" quota is available in the Service Quotas console, but only in the us-east-1 region that acts as the primary region for IAM in the main commercial partition.

Apparently this is often misunderstood or not well-documented, especially for AWS SSO permission sets. AWS Support sometimes struggles with this because the limit applies indirectly to the IAM roles that AWS SSO creates.

More on this ... The quota for attaching managed policies to a permission set is part of the IAM role limits (since AWS SSO creates IAM roles under the hood for permission sets). However, this specific quota is not visible in the Service Quotas console. ... so ... I need to increase the number of managed policies attached to an IAM role for AWS SSO permission sets from 10 to 20. This is to accommodate specific permission requirements in our organization. Please let me know if additional details are required.